National Park Passports

We were just talking in studio about environmental and historic education, an area in which the National Park Service has some expertise.  One of the programs the used to get people to settle into a park and take it seriously is the Junior Ranger program.  To get their badge, junior rangers often have to complete a series of activities, attend a ranger-led talk/hike, answer questions, etc.  For some families, it forces them to see and experience parts of the parks they wouldn't have otherwise.

The other is the National Parks Passports program, which let's you stamp your passport booklet at each park you visit.   This program gets visitors to go to more parks, and more obscure parks.  Some passport junkies have posted their stories and and nearly complete collections of passport stamps.Maybe these don't translate well to our local parks.  But what is the equivalent?  What would get people more engaged here?